The SIM900A Mini is a compact GSM/GPRS module that enables cellular communication in embedded systems. It allows devices to send and receive SMS messages, make and receive voice calls, and connect to the internet via GPRS. This module is widely used in various applications such as remote data monitoring, IoT devices, automotive applications, and security systems.
This circuit interfaces an Arduino UNO with a SIM900A GSM module. The Arduino controls the SIM900A via digital pins D9 and D10 for serial communication, while both components share a common ground.
Open Project in Cirkit Designer
This circuit interfaces an Arduino UNO with a SIM900A GSM module. The Arduino communicates with the SIM900A via digital pins D9 and D10 for serial data transmission and reception, while both devices share a common ground.
Open Project in Cirkit Designer
This circuit features an Arduino UNO microcontroller interfaced with a SIM900A GSM module and a GPS NEO 6M module. The Arduino communicates with the SIM900A via digital pins D7 and D8 for TXD and RXD respectively, and with the GPS module via digital pins D3 and D4 for RX and TX. Additionally, a Piezo Sensor is connected to analog pin A0, allowing the Arduino to read vibrations or pressure changes.
Open Project in Cirkit Designer
This circuit integrates an Arduino UNO with a SIM900A GSM module, powered by a 12V power supply. The Arduino communicates with the SIM900A via digital pins D4 and D5 for TX and RX respectively, enabling GSM communication capabilities.
Open Project in Cirkit Designer| Pin Number | Name | Description |
|---|---|---|
| 1 | VCC | Power supply input (3.4V - 4.5V) |
| 2 | RST | Reset pin, active low |
| 3 | RXD | Serial data receive pin |
| 4 | TXD | Serial data transmit pin |
| 5 | GND | Ground connection |
#include <SoftwareSerial.h>
SoftwareSerial SIM900A(7, 8); // RX, TX
void setup() {
// Begin serial communication with Arduino and Arduino IDE (Serial Monitor)
Serial.begin(9600);
// Begin serial communication with SIM900A Mini and set baud rate
SIM900A.begin(9600);
// AT command to set SIM900A to SMS mode
SIM900A.print("AT+CMGF=1\r");
delay(100);
// Set module to send SMS data to serial out upon receipt
SIM900A.print("AT+CNMI=2,2,0,0,0\r");
delay(100);
}
void loop() {
// Check if the SIM900A Mini has sent any data to the Arduino
if (SIM900A.available()) {
Serial.write(SIM900A.read()); // Forward what SIM900A Mini has sent to Serial Monitor
}
// Check if the Arduino has sent any data to the SIM900A Mini
if (Serial.available()) {
SIM900A.write(Serial.read()); // Forward what Serial Monitor has sent to SIM900A Mini
}
}
Note: This example sets up the SIM900A Mini to send and receive SMS messages. The SoftwareSerial library is used to create a serial connection on pins 7 and 8 of the Arduino UNO. Adjust the pin numbers as needed for your setup.